Key derivation for a module using an embedded universal integrated circuit card

A method for a module using an embedded integrated circuit card (eUICC) to support authentication, the method comprising the module:

• reading a module identity from a protected memory and sending the module identity to an eUICC subscription manager;
• receiving a first profile for the eUICC, wherein the first profile includes a first network module identity and a first key K;
• using the eUICC, the first network module identity, and the first key K to authenticate with a first wireless network,
• sending to an eUICC subscription manager an algorithm token for a shared secret algorithm after authenticating with the first key K, wherein the module uses an asymmetric ciphering algorithm to encrypt the algorithm token;
• deriving a shared secret key using the algorithm token and the shared secret algorithm, wherein the shared secret algorithm includes a secure hash algorithm and a component parameter;
• receiving a second profile for the eUICC, wherein the module decrypts the second profile using the derived shared secret key, wherein the decrypted second profile includes a second network module identity and a second key K;
• and
• authenticating with a second wireless network using the second network module identity and the second key K.

A method for a module to send a sensor measurement, the method comprising the module:

• recording in a protected memory a first module private key, a first module public key, a server public key, and a module identity;
• sending (i) the module identity and (ii) a module digital signature to a server for an embedded universal integrated circuit card (eUICC) subscription manager, wherein the module uses the first module private key for the module digital signature, and wherein the module sends from an Internet Protocol address and port (IP:port) number;
• receiving a response at the IP:port number, wherein the response includes a server digital signature and a first shared secret key, wherein the module verifies the server digital signature using the server public key, wherein the first shared secret key is decrypted with an asymmetric ciphering algorithm and the first module private key;
• deriving a second shared secret key using (i) a shared secret algorithm and (ii) the received first shared secret key as a random number for the shared secret algorithm, wherein the shared secret algorithm uses a secure hash algorithm;
• receiving (i) a set of cryptographic parameters, and (ii) a profile for an eUICC, wherein the profile is decrypted using the derived second shared secret key;
• deriving a second module public key and a second module private key using the set of cryptographic parameters;
• selecting the received profile before authenticating with a wireless network;
• sending a message with the second module public key and the module identity, wherein the module authenticates using the first module private key;
• and,
• sending the sensor measurement in a module encrypted data, wherein the module uses the second module private key to encrypt the module encrypted data.